ACTIVE EPILEPSY IN MENTALLY-RETARDED CHILDREN .1. PREVALENCE AND ADDITIONAL NEUROIMPAIRMENTS

A population-based study of active epilepsy was conducted in 6-13-year -old mentally retarded children born between 1975 and 1986. The popula tion at risk comprised 48 873 children. Ninety-eight children were ide ntified, 35 mildly and 63 severely retarded. The prevalence was 2.0 pe r 1000; 0.7 per 1000 for mildly and 1.3 per 1000 for severely retarded children. Sixty-nine children had at least one additional neuroimpair ment. Cerebral palsy was found in 42 children with a majority of spast ic/dystonic tetraplegias; visual impairment was present in 24 and auti sm in 24. Thirty-three children had only a mild or no gross motor disa bility and mild mental retardation, while 23 had IQs < 20 and a very s evere gross motor disability. This study underlines the fact that acti ve epilepsy in mentally retarded children is often associated with add itional neuroimpairments, especially a combination of severe cerebral palsy and severe visual impairment.